The invention provides a device and method for hair transplantation, and in particular to the formation of incisions for receiving small grafts of hair.
For many individuals, hair loss can be undesirable or even traumatic. For such individuals, many hair replacement alternatives have been proposed including wigs, hair pieces, and more recently hair transplants. To some individuals, the hair transplant alternative is particularly desirable because living hair can be used to cover bald areas. As methods for hair transplantation continue to improve, this hair replacement alternative is becoming more widely accepted.
In a typical hair transplantation procedure, grafts of skin containing hair are removed from the individual and are transplanted to other areas. To place the grafts into these areas, a number of incisions are made in the scalp. The incisions are then cleaned and a graft is inserted into each incision. When placing the grafts into the incisions, the surgeon attempts to arrange the grafts so that the resulting transplant resembles a normal hairline. To accomplish such a task, it is desirable in some cases to place only a small number of hairs, i.e. 2 to 6, often referred to as a minigraft (or even a single hair, referred to as a micrograft) into the incisions.
Over the years, a variety of techniques have been employed to transplant minigrafts. In one attempt, the use of a dilator has been proposed. According to this method, an 18 or 20 gauge hypodermic needle is employed to form an incision. A dilator is then placed in the incision to dilate the incision. After removal of the dilator, the minigraft is inserted. Over time, the incision shrinks so that the skin will support the graft. However, until the incision shrinks, the graft is unstable and can be displaced.
In other proposed methods, punches have been employed to punch a small diameter hole in the scalp. The graft is then placed in the cylindrical opening left by the punch. In yet another proposed method, a #11 blade (a Lancet blade) has been employed to form an incision for receiving a minigraft. Since the Lancet blade is angled, this method includes the additional step of translating the blade downward at an angle of 45.degree. after the initial insertion so that the bottom of the incision has a constant depth. Having a constant depth is desirable so that the hair follicles in the graft will all be transplanted at the same depth. In a similar procedure, the use of a No-Kor vented needle (Becton Dickinson and Co, Rutherford, N.J.) has been proposed for creating incisions for receiving 1 to 3 haired minigrafts. Such a method is described in, Dominic A. Brandy and Michael Meshkin, Utilization of No-Kor Needles For Slit-micrografting, J Dermatol Surg Oncol, 20:336-339 (1994).
One problem associated with the above procedures is how to control the depth of the incisions. Usually, this is done visually by the surgeon when inserting the blade or punch. However, such constant visual inspection is both time consuming and tedious to the surgeon. Although the Lancet blade is angled to allow easier visual identification of the depth of the cut, use of such a blade still requires the blade to be angled downward so that the incision has a uniform depth. Such a procedure is both time consuming and inconvenient. One particular problem experienced with the use of punches is that the central lumen of the punch often becomes clogged with tissue. The punch then loses its effectiveness until the tissue is removed.
It would therefore be desirable to provide a device and method that could substantially reduce or eliminate such problems. Such a device and method should allow the depth of the incision to be easily and conveniently controlled and should not require substantial manipulation of the blade to form an incision having a constant depth. In the case of punches, the device and method should additionally allow for the creation of a plurality of incisions without having the punch becoming clogged with tissue.